Simultaneous touch sensor scanning and display refreshing for display-embedded touch sensors

ABSTRACT

In one embodiment, a method includes receiving a request to refresh a display for a refresh period, wherein the display is coupled to a touch sensor operable to detect touch input at the display. During a first phase of the refresh period, a first portion of the display is refreshed while the touch sensor a second portion and a third portion of the display is activated. The second portion and the third portion are a half screen distance apart. During a second phase of the refresh period, the second portion of the display is refreshed while the touch sensor at a fourth portion and a fifth portion of the display is activated. The fourth portion and the fifth portion are a half screen distance apart.

RELATED APPLICATION

This application is a continuation under 35 U.S.C. §120 of U.S.application Ser. No. 13/827,713, filed Mar. 14, 2013 and entitled“Simultaneous Touch Sensor Scanning and Display Refreshing forMinimizing Display Degradation for Display-Embedded Touch Sensors,”which is incorporated herein by reference.

TECHNICAL FIELD

This disclosure generally relates to touch sensors, and moreparticularly to touch sensor scanning for display-embedded touchsensors.

BACKGROUND

Touch sensing using a sensor embedded in a display may be typicallycarried out during periods when the display is not being updated.However, current approaches for doing this may be limited. For example,the amount of time available for carrying out a scan of the touch sensoris limited by the amount of time necessary for display updating. Thus,the flexibility to employ techniques that avoid or suppress externalnoise is limited. As another example, the frequency at which the touchcontroller can provide updates of touches to the host may be limited dueto the increased amount of time between successive touch sensor scans.These constraints may degrade the touch controller performance in waysthat are undesirable to the end user experience.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example touch sensor according to particularembodiments of the present disclosure;

FIGS. 2A-2B illustrate an example display-embedded touch sensoraccording to particular embodiments of the present disclosure;

FIGS. 3A-3D illustrate example phases of a display refresh cycle for thedisplay-embedded touch sensor of FIGS. 2A-2B according to particularembodiments of the present disclosure;

FIG. 4 illustrates an example method for touch sensor scanning of thedisplay-embedded touch sensor of FIG. 2A-2B according to particularembodiments of the present disclosure; and

FIG. 5 illustrates an example computer system for use with thedisplay-embedded touch sensors of FIGS. 2A-2B according to particularembodiments of the present disclosure.

DESCRIPTION OF EXAMPLE EMBODIMENTS

Touch sensing using a sensor embedded in a display, such as an LCDscanning display, may be synchronized to times when the display is notbeing updated (and may be referred to as the “blanking periods”).Because the display and touch functions often share common circuitry orwiring, the display update function and touch sensing function may bemutually exclusive. If they are not mutually exclusive, degradation ofthe displayed image or touch sensing performance may be observed.

Currently, touch sensing using a sensor embedded in a display may becarried out during periods when the display is not being updated.However, current approaches for doing this may be limited. For example,the amount of time available for carrying out a scan of the touch sensoris limited by the amount of time necessary for display updating. Thus,the flexibility to employ techniques that avoid or suppress externalnoise is limited. As another example, the frequency at which the touchcontroller can provide updates of touches to the host may be limited dueto the increased amount of time between successive touch sensor scans.These constraints may degrade the touch controller performance in waysthat are undesirable to the end user experience.

Accordingly, aspects of the present disclosure include a method ofscanning a touch sensor, such as a capacitive touch sensor, embedded ina display, such as an LCD scanning display (e.g., an active matrixdisplay), that allows touch sensing to be carried out while the displayis being updated without causing degradation to the displayed imagequality. Since display degradation normally occurs when touch sensing iscarried out at the same time and in the same region that the display isbeing updated, the display degradation may be avoided by employingsynchronization between the display and the touch sensing controllerthat ensures that touch sensing cannot be carried out at the same timeand in the same region that the display is being updated.

By allowing touch sensing to be carried out at the same time as displayupdate, the present disclosure may remove the majority of constraintsassociated with the synchronized touch sensing techniques normallyemployed when using a touch sensor embedded in a display. As oneexample, the present disclosure allows for more flexibility in theimplementation of noise suppression and noise avoidance schemes by thetouch controller. In addition, the present disclosure provides much moretime for touch scanning because touch scanning is permitted duringdisplay update. This additional time may be used to implement moresophisticated noise avoidance and suppression techniques such asfrequency hoping and increased sample filtering.

As another example, the present disclosure allows for higher touchreport rates for touch sensing schemes directly synchronized to displayupdate rates. In conventional synchronized schemes, touch sensing may belinked directly to the display update rate, which may be 60 Hz. However,implementation of an optimal touch sensing user interface normallyrequires a report rate in excess of 100 Hz. The present disclosureprovides more flexibility and time for touch sensing, which will allowfor the touch sensor to be scanned at twice per display update,providing an effective report rate of 120 Hz and optimizing the userexperience.

FIG. 1 illustrates an example touch sensor 110 with an exampletouch-sensor controller 112. Touch sensor 110 and touch-sensorcontroller 112 may detect the presence and location of a touch or theproximity of an object within a touch-sensitive area of touch sensor110. Herein, reference to a touch sensor may encompass both the touchsensor and its touch-sensor controller, where appropriate. Similarly,reference to a touch-sensor controller may encompass both thetouch-sensor controller and its touch sensor, where appropriate. Touchsensor 110 may include one or more touch-sensitive areas, whereappropriate. Touch sensor 110 may include an array of drive and senseelectrodes (or an array of electrodes of a single type) disposed on oneor more substrates, which may be made of a dielectric material. Herein,reference to a touch sensor may encompass both the electrodes of thetouch sensor and the substrate(s) that they are disposed on, whereappropriate. Alternatively, where appropriate, reference to a touchsensor may encompass the electrodes of the touch sensor, but not thesubstrate(s) that they are disposed on.

An electrode (whether a ground electrode, a guard electrode, a driveelectrode, or a sense electrode) may be an area of conductive materialforming a shape, such as for example a disc, square, rectangle, thinline, other suitable shape, or suitable combination of these. One ormore cuts in one or more layers of conductive material may (at least inpart) create the shape of an electrode, and the area of the shape may(at least in part) be bounded by those cuts. In particular embodiments,the conductive material of an electrode may occupy approximately 100% ofthe area of its shape. As an example and not by way of limitation, anelectrode may be made of indium tin oxide (ITO) and the ITO of theelectrode may occupy approximately 100% of the area of its shape(sometimes referred to as 100% fill), where appropriate. In particularembodiments, the conductive material of an electrode may occupysubstantially less than 100% of the area of its shape. As an example andnot by way of limitation, an electrode may be made of fine lines ofmetal or other conductive material (FLM), such as for example copper,silver, or a copper- or silver-based material, and the fine lines ofconductive material may occupy approximately 5% of the area of its shapein a hatched, mesh, or other suitable pattern. Herein, reference to FLMencompasses such material, where appropriate. Although this disclosuredescribes or illustrates particular electrodes made of particularconductive material forming particular shapes with particular fillpercentages having particular patterns, this disclosure contemplates anysuitable electrodes made of any suitable conductive material forming anysuitable shapes with any suitable fill percentages having any suitablepatterns.

Where appropriate, the shapes of the electrodes (or other elements) of atouch sensor may constitute in whole or in part one or moremacro-features of the touch sensor. One or more characteristics of theimplementation of those shapes (such as, for example, the conductivematerials, fills, or patterns within the shapes) may constitute in wholeor in part one or more micro-features of the touch sensor. One or moremacro-features of a touch sensor may determine one or morecharacteristics of its functionality, and one or more micro-features ofthe touch sensor may determine one or more optical features of the touchsensor, such as transmittance, refraction, or reflection.

A mechanical stack may contain the substrate (or multiple substrates)and the conductive material limning the drive or sense electrodes oftouch sensor 110. As an example and not by way of limitation, themechanical stack may include a first layer of optically clear adhesive(OCA) beneath a cover panel. The cover panel may be clear and made of aresilient material suitable for repeated touching, such as for exampleglass, polycarbonate, or poly(methyl methacrylate) (PMMA). Thisdisclosure contemplates any suitable cover panel made of any suitablematerial. The first layer of OCA may be disposed between the cover paneland the substrate with the conductive material forming the drive orsense electrodes. The mechanical stack may also include a second layerof OCA and a dielectric layer (which may be made of PET or anothersuitable material, similar to the substrate with the conductive materialforming the drive or sense electrodes). As an alternative, whereappropriate, a thin coating of a dielectric material may be appliedinstead of the second layer of OCA and the dielectric layer. The secondlayer of OCA may be disposed between the substrate with the conductivematerial making up the drive or sense electrodes and the dielectriclayer, and the dielectric layer may be disposed between the second layerof OCA and an air gap to a display of a device including touch sensor110 and touch-sensor controller 112. As an example only and not by wayof limitation, the cover panel may have a thickness of approximately 1mm; the first layer of OCA may have a thickness of approximately 0.05mm; the substrate with the conductive material forming the drive orsense electrodes may have a thickness of approximately 0.05 mm; thesecond layer of OCA may have a thickness of approximately 0.05 mm; andthe dielectric layer may have a thickness of approximately 0.05 mm.Although this disclosure describes a particular mechanical stack with aparticular number of particular layers made of particular materials andhaving particular thicknesses, this disclosure contemplates any suitablemechanical stack with any suitable number of any suitable layers made ofany suitable materials and having any suitable thicknesses. As anexample and not by way of limitation, in particular embodiments, a layerof adhesive or dielectric may replace the dielectric layer, second layerof OCA, and air gap described above, with there being no air gap to thedisplay. As another example, the mechanical stack may include the layersshown in FIGS. 2A-2B and described further below.

One or more portions of the substrate of touch sensor 110 may be made ofpolyethylene terephthalate (PET), glass, or another suitable material.This disclosure contemplates any suitable substrate with any suitableportions made of any suitable material. In particular embodiments, thedrive or sense electrodes in touch sensor 110 may be made of ITO inwhole or in part. In particular embodiments, the drive or senseelectrodes in touch sensor 110 may be made of fine lines of metal orother conductive material. As an example and not by way of limitation,one or more portions of the conductive material may be copper orcopper-based and have a thickness of approximately 5 μm or less and awidth of approximately 10 μm or less. As another example, one or moreportions of the conductive material may be silver or silver-based andsimilarly have a thickness of approximately 5 μm or less and a width ofapproximately 10 μm or less. This disclosure contemplates any suitableelectrodes made of any suitable material.

Touch sensor 110 may implement a capacitive form of touch sensing. In amutual-capacitance implementation, touch sensor 110 may include an arrayof drive and sense electrodes forming an array of capacitive nodes. Adrive electrode and a sense electrode may form a capacitive node. Thedrive and sense electrodes forming the capacitive node may come neareach other, but not make electrical contact with each other. Instead,the drive and sense electrodes may be capacitively coupled to each otheracross a space between them. A pulsed or alternating voltage applied tothe drive electrode (by touch-sensor controller 112) may induce a chargeon the sense electrode, and the amount of charge induced may besusceptible to external influence (such as a touch or the proximity ofan object). When an object touches or comes within proximity of thecapacitive node, a change in capacitance may occur at the capacitivenode and touch-sensor controller 112 may measure the change incapacitance. By measuring changes in capacitance throughout the array,touch-sensor controller 112 may determine the position of the touch orproximity within the touch-sensitive area(s) of touch sensor 110.

In a self-capacitance implementation, touch sensor 110 may include anarray of electrodes of a single type that may each form a capacitivenode. When an object touches or comes within proximity of the capacitivenode, a change in self-capacitance may occur at the capacitive node andtouch-sensor controller 112 may measure the change in capacitance, forexample, as a change in the amount of charge needed to raise the voltageat the capacitive node by a pre-determined amount. As with amutual-capacitance implementation, by measuring changes in capacitancethroughout the array, touch-sensor controller 112 may determine theposition of the touch or proximity within the touch-sensitive area(s) oftouch sensor 110. This disclosure contemplates any suitable form ofcapacitive touch sensing, where appropriate.

In particular embodiments, one or more drive electrodes may togetherform a drive line running horizontally or vertically or in any suitableorientation. Similarly, one or more sense electrodes may together form asense line running horizontally or vertically or in any suitableorientation. In particular embodiments, drive lines may runsubstantially perpendicular to sense lines. Herein, reference to a driveline may encompass one or more drive electrodes making up the driveline, and vice versa, where appropriate. Similarly, reference to a senseline may encompass one or more sense electrodes making up the senseline, and vice versa, where appropriate.

Although this disclosure describes particular configurations ofparticular electrodes forming particular nodes, this disclosurecontemplates any suitable configuration of any suitable electrodesforming any suitable nodes. Moreover, this disclosure contemplates anysuitable electrodes disposed on any suitable number of any suitablesubstrates in any suitable patterns.

As described above, a change in capacitance at a capacitive node oftouch sensor 110 may indicate a touch or proximity input at the positionof the capacitive node. Touch-sensor controller 112 may detect andprocess the change in capacitance to determine the presence and locationof the touch or proximity input. Touch-sensor controller 112 may thencommunicate information about the touch or proximity input to one ormore other components (such one or more central processing units (CPUs))of a device that includes touch sensor 110 and touch-sensor controller112, which may respond to the touch or proximity input by initiating afunction of the device (or an application running on the device).Although this disclosure describes a particular touch-sensor controllerhaving particular functionality with respect to a particular device anda particular touch sensor, this disclosure contemplates any suitabletouch-sensor controller having any suitable functionality with respectto any suitable device and any suitable touch sensor.

Touch-sensor controller 112 may be one or more integrated circuits(ICs), such as for example general-purpose microprocessors,microcontrollers, programmable logic devices or arrays,application-specific ICs (ASICs). In particular embodiments,touch-sensor controller 112 comprises analog circuitry, digital logic,and digital non-volatile memory. In particular embodiments, touch-sensorcontroller 112 is disposed on a flexible printed circuit (FPC) bonded tothe substrate of touch sensor 110, as described below. The FPC may beactive or passive, where appropriate. In particular embodiments,multiple touch-sensor controllers 112 are disposed on the FPC.Touch-sensor controller 112 may include a processor unit, a drive unit,a sense unit, and a storage unit. The drive unit may supply drivesignals to the drive electrodes of touch sensor 110. The sense unit maysense charge at the capacitive nodes of touch sensor 110 and providemeasurement signals to the processor unit representing capacitances atthe capacitive nodes. The processor unit may control the supply of drivesignals to the drive electrodes by the drive unit and processmeasurement signals from the sense unit to detect and process thepresence and location of a touch or proximity input within thetouch-sensitive area(s) of touch sensor 110. The processor unit may alsotrack changes in the position of a touch or proximity input within thetouch-sensitive area(s) of touch sensor 110. The storage unit may storeprogramming for execution by the processor unit, including programmingfor controlling the drive unit to supply drive signals to the driveelectrodes, programming for processing measurement signals from thesense unit, and other suitable programming, where appropriate. Althoughthis disclosure describes a particular touch-sensor controller having aparticular implementation with particular components, this disclosurecontemplates any suitable touch-sensor controller having any suitableimplementation with any suitable components.

Tracks 114 of conductive material disposed on the substrate of touchsensor 110 may couple the drive or sense electrodes of touch sensor 110to connection pads 116, also disposed on the substrate of touch sensor110. As described below, connection pads 116 facilitate coupling oftracks 114 to touch-sensor controller 112. Tracks 114 may extend into oraround (e.g. at the edges of) the touch-sensitive area(s) of touchsensor 110. Particular tracks 114 may provide drive connections forcoupling touch-sensor controller 112 to drive electrodes of touch sensor110, through which the drive unit of touch-sensor controller 112 maysupply drive signals to the drive electrodes. Other tracks 114 mayprovide sense connections for coupling touch-sensor controller 112 tosense electrodes of touch sensor 110, through which the sense unit oftouch-sensor controller 112 may sense charge at the capacitive nodes oftouch sensor 110. Tracks 114 may be made of fine lines of metal or otherconductive material. As an example and not by way of limitation, theconductive material of tracks 114 may be copper or copper-based and havea width of approximately 100 μm or less. As another example, theconductive material of tracks 114 may be silver or silver-based and havea width of approximately 100 μm or less. In particular embodiments,tracks 114 may be made of ITO in whole or in part in addition or as analternative to fine lines of metal or other conductive material.Although this disclosure describes particular tracks made of particularmaterials with particular widths, this disclosure contemplates anysuitable tracks made of any suitable materials with any suitable widths.In addition to tracks 114, touch sensor 110 may include one or moreground lines terminating at a ground connector (which may be aconnection pad 116) at an edge of the substrate of touch sensor 110(similar to tracks 114).

Connection pads 116 may be located along one or more edges of thesubstrate, outside the touch-sensitive area(s) of touch sensor 110. Asdescribed above, touch-sensor controller 112 may be on an FPC.Connection pads 116 may be made of the same material as tracks 114 andmay be bonded to the FPC using an anisotropic conductive film (ACF).Connection 118 may include conductive lines on the FPC couplingtouch-sensor controller 112 to connection pads 116, in turn couplingtouch-sensor controller 112 to tracks 114 and to the drive or senseelectrodes of touch sensor 110. In another embodiment, connection pads116 may be connected to an electro-mechanical connector (such as a zeroinsertion force wire-to-board connector); in this embodiment, connection118 may not need to include an FPC. This disclosure contemplates anysuitable connection 118 between touch-sensor controller 112 and touchsensor 110.

FIGS. 2A-2B illustrate an example display-embedded touch sensor stack200. In particular embodiments, touch sensor 200 may include, withoutlimitation, a thin film transistor (TFT) substrate 214, TFT layer 212,transmit electrodes 210, display medium 208 (e.g. a liquid crystaldisplay (LCD)), color filter 206, receive electrodes 204, and coversubstrate 202 as shown in FIG. 2A. TFT layer 212 may include one or moreelectronic components (e.g., transistors) suitable for powering and/orcontrolling display medium 208. In particular embodiments, TFT substrate214 may be the substrate for both TFT layer 212 and transmit electrodes210, and may be approximately 0.4 mm thick. Similarly, in particularembodiments, cover substrate 202 may be the substrate for receiveelectrodes 204 and color filter 206, and may comprise glass and beapproximately 0.2-0.4 mm thick. Other suitable layers may be added totouch sensor stack 200 or some layers may be removed from touch sensorstack 200 as necessary in other embodiments. FIG. 2B illustrates analternative perspective of the view shown in FIG. 2A, with the receiveelectrodes 204 and transmit electrodes 210 intersecting one another,such as in a capacitive touch sensor configuration.

In display-embedded touch sensors, such as touch sensor stack 200, thetouch sensing components and the display components may share certainelectronic. For example, the transmit electrodes 210 may also act as thereference voltage source for the display components (e.g., TFT layer212) of touch sensor 200. However, when activating the touch sensingfunctions of the display-embedded sensor, a pulse voltage may be appliedto the transmit electrodes 210. This additional pulse voltage in thereference voltage of the display circuit may thus cause displaydegradation when touch sensing is carried out at the same time and inthe same region that the display is being updated. Display degradationmay be avoided, however, by employing synchronization between thedisplay and the touch sensing controller that ensures that touch sensingis not carried out at the same time and in the same region that thedisplay is being updated, as shown in FIGS. 3A-3D and FIG. 4 andexplained further below.

FIGS. 3A-3D illustrate example phases of a display refresh cycle for thedisplay-embedded touch sensor of FIGS. 2A-2B. Although a display updateis considered to be a continuous update across a screen, for purposes ofsensing schemes according to embodiments of the present disclosure, thedisplay may be divided into multiple sections and the display update maybe considered to have a number of phases. In particular embodiments, thenumber of display phases may equal the number of display sections. Forinstance, in the illustrated example of FIGS. 3A-3D, the display isdivided into four sections (quadrants) and the display refresh cycle hasfour phases. Any suitable number of display divisions and/or number ofrefresh phases may be used, however. For example, in some embodiments,the display may be divided into six sections while the display refreshmay have six phases. As another example, in some embodiments, thedisplay may be divided into eight sections while the display refresh mayhave eight phases.

FIG. 3A represents the first phase of the display refresh cycle. Duringthe first phase of the refresh cycle, the first quadrant of the displaymay refresh (i.e., do not receive a pulse voltage at transmit electrodes210) while the transmit electrodes in the second and fourth quadrantsscan for touch input (i.e., receive a pulse voltage at transmitelectrodes 210). During the second phase of the display refresh cycle,as shown in FIG. 3B, the second quadrant of the display may refreshwhile the transmit electrodes in the first and third quadrants scan fortouch input. During the third phase of the display refresh cycle, asshown in FIG. 3C, the third quadrant of the display may refresh whilethe transmit electrodes in the second and fourth quadrants scan fortouch input again. During the fourth phase of the display refresh cycle,as shown in FIG. 3D, the fourth quadrant of the display may refreshwhile the transmit electrodes in the first and third quadrants scan fortouch input again.

One of skill in the art will recognize that the touch sensor of FIGS.3A-3D will scan for touch input at a rate that is twice the displayupdate frequency. Thus, in a display with a typical refresh rate of 60Hz, the touch input report rate would be 120 Hz, which is well above anoptimal report rate of 100 Hz. As explained above, in conventionalsynchronized touch sensing schemes in display-embedded touch sensors,touch sensing may be linked directly to the display update rate, whichin this example would be 60 Hz and below the optimal minimum report rateof 100 Hz. Thus, aspects of the present disclosure may provide moreoptimal touch sensing feedback over conventional synchronizeddisplay-embedded touch sensors while also minimizing any displaydegradation that is caused by updating the display and sensing touchinput simultaneously.

FIG. 4 illustrates an example method for touch sensor scanning of thedisplay-embedded touch sensor of FIG. 2A-2B. The method 400 may start atstep 410, where a request to refresh or update the display is received.The request may be, for example and without limitation, a pulse voltagesent by a controller or processor coupled to the display-embedded touchsensor.

At step 420, a first portion of the display may be refreshed while thetouch electrodes at a second portion of the display are activated. Thisstep may take place during any portion of a display refresh period. Forexample, referring to the above example with four display refresh periodportions, step 420 may take place in any of the four portions (e.g.,those shown in FIGS. 3A-3D). In other words, the first portion of adisplay refresh period may be shown by FIG. 3A in some embodiments,while the first portion of a display refresh period may be shown by FIG.3B in other embodiments. In particular embodiments, the first and secondportions may be different from one another. In some embodiments, thefirst portion of the display may be adjacent to the second portion ofthe display, in whole or in part. For example, referring to FIG. 3A, thefirst portion of the display may be Quadrant 1, and the second portionof the display may be Quadrants 2 and 4. In this example, the first andsecond portions may be considered adjacent in part. Refreshing the firstportion of the display may include, for example, sending a voltagesignal to the pixels of the display located in the first portion.Activating the touch electrodes in the second portion of the display mayinclude, for example, sending voltage pulses through the transmitelectrodes of the touch sensor located in the second portion.

At step 430, a third portion of the display may be refreshed while thetouch electrodes at a fourth portion of the display are activated. Inparticular embodiments, the third and fourth portions may be differentfrom one another. In some embodiments, the third portion of the displaymay be adjacent to the fourth portion of the display, in whole or inpart. For example, referring to FIG. 3B, the third portion of thedisplay may be Quadrant 2, and the fourth portion of the display may beQuadrants 1 and 3. In this example, the third and fourth portions may beconsidered adjacent in whole.

At step 440, a fifth portion of the display may be refreshed while thetouch electrodes at a second portion of the display are activated. Inparticular embodiments, the fifth and second portions may be differentfrom one another. In some embodiments, the fifth portion of the displaymay be adjacent to the second portion of the display, in whole or inpart. For example, referring to FIG. 3C, the fifth portion of thedisplay may be Quadrant 3, and the second portion of the display may beQuadrants 2 and 4. In this example, the fifth and second portions may beconsidered adjacent in whole.

At step 450, a sixth portion of the display may be refreshed while thetouch electrodes at a fourth portion of the display are activated. Inparticular embodiments, the sixth and fourth portions may be differentfrom one another. In some embodiments, the sixth portion of the displaymay be adjacent to the fourth portion of the display, in whole or inpart. For example, referring to FIG. 3D, the sixth portion of thedisplay may be Quadrant 4, and the fourth portion of the display may beQuadrants 1 and 3. In this example, the sixth and fourth portions may beconsidered adjacent in part.

Particular embodiments may repeat the steps of the method of FIG. 4,where appropriate. Moreover, although this disclosure describes andillustrates particular steps of the method of FIG. 4 as occurring in aparticular order, this disclosure contemplates any suitable steps of themethod of FIG. 4 occurring in any suitable order. Furthermore, althoughthis disclosure describes and illustrates particular components,devices, or systems carrying out particular steps of the method of FIG.4, this disclosure contemplates any suitable combination of any suitablecomponents, devices, or systems carrying out any suitable steps of themethod of FIG. 4.

In addition, although the example method 400 of FIG. 4 describes adisplay divided into four quadrants and a display refresh cycle withfour phases, any suitable number of display divisions and/or refreshphases are contemplated in the present disclosure. For example, method400 may be adapted to an embodiment with eight display divisions andeight refresh phases. In such embodiments, the first portion of thedisplay in step 420 may be section 1 of the eight display sections, andthe second portion of the display may be sections 2 and 6. In step 430,the third portion of the display may be section 2 and the fourth portionof the display may be sections 1 and 5. Step 440 may therefore includerefreshing a fifth portion of the display while activating the touchelectrodes at a sixth portion of the display. (i.e., instead ofactivating the touch electrodes at the second portion as describedabove). The fifth portion of the display may be section 3 and the sixthportion may be sections 4 and 8. Step 450 may thus include refreshing aseventh portion of the display while activating the touch electrodes atan eighth portion of the display. The seventh portion may be section 4and the eighth portion may be sections 3 and 7. In such embodiments, themethod may continue in this pattern through additional steps until eachdisplay section of eight has been refreshed.

One of skill in the art will recognize that the method 400 (for anynumber of display sections) will scan for touch input at a rate that istwice the display update frequency. Thus, in a display with a refreshrate of 60 Hz, the touch input report rate would be 120 Hz, which iswell above an optimal report rate of 100 Hz. One of skill in the artwill also recognize that certain embodiments may allow for the two touchsensor regions being activated to be a half screen distance apart. Forexample, in the example shown in FIGS. 3A-3D, each region where thetouch sensors are activated is two sections away from the other regionwhere the touch sensors are being activated, which is half of the amountof display divisions (i.e., four display divisions). As another example,in the embodiment described above with eight display sections, eachregion where the touch sensors are being activated is four regions awayfrom the other region where touch sensors are being activated, which isagain half of the amount of display sections (i.e., eight displaysections).

FIG. 5 illustrates an example computer system 500 for use with thedisplay-embedded touch sensors of FIGS. 2A-2B. In particularembodiments, one or more computer systems 500 perform one or more stepsof one or more methods described or illustrated herein. In particularembodiments, one or more computer systems 500 provide functionalitydescribed or illustrated herein. In particular embodiments, softwarerunning on one or more computer systems 500 performs one or more stepsof one or more methods described or illustrated herein or providesfunctionality described or illustrated herein. In particularembodiments, the software running on one or more computer systems 500may be logic encoded on a computer readable medium. Particularembodiments include one or more portions of one or more computer systems500. Herein, reference to a computer system may encompass a computingdevice, and vice versa, where appropriate. Moreover, reference to acomputer system may encompass one or more computer systems, whereappropriate.

This disclosure contemplates any suitable number of computer systems500. This disclosure contemplates computer system 500 taking anysuitable physical for in. As example and not by way of limitation,computer system 500 may be an embedded computer system, a system-on-chip(SOC), a single-board computer system (SBC) (such as, for example, acomputer-on-module (COM) or system-on-module (SOM)), a desktop computersystem, a laptop or notebook computer system, an interactive kiosk, amainframe, a mesh of computer systems, a mobile telephone, a personaldigital assistant (PDA), a server, a tablet computer system, or acombination of two or more of these. Where appropriate, computer system500 may include one or more computer systems 500; be unitary ordistributed; span multiple locations; span multiple machines; spanmultiple data centers; or reside in a cloud, which may include one ormore cloud components in one or more networks. Where appropriate, one ormore computer systems 500 may perform without substantial spatial ortemporal limitation one or more steps of one or more methods describedor illustrated herein. As an example and not by way of limitation, oneor more computer systems 500 may perform in real time or in batch modeone or more steps of one or more methods described or illustratedherein. One or more computer systems 500 may perform at different timesor at different locations one or more steps of one or more methodsdescribed or illustrated herein, where appropriate.

In particular embodiments, computer system 500 includes a processor 502,memory 504, storage 506, an input/output (I/O) interface 508, acommunication interface 510, and a bus 512. Although this disclosuredescribes and illustrates a particular computer system having aparticular number of particular components in a particular arrangement,this disclosure contemplates any suitable computer system having anysuitable number of any suitable components in any suitable arrangement.

In particular embodiments, processor 502 includes hardware for executinginstructions, such as those making up a computer program. As an exampleand not by way of limitation, to execute instructions, processor 502 mayretrieve (or fetch) the instructions from an internal register, aninternal cache, memory 504, or storage 506; decode and execute them; andthen write one or more results to an internal register, an internalcache, memory 504, or storage 506. In particular embodiments, processor502 may include one or more internal caches for data, instructions, oraddresses. This disclosure contemplates processor 502 including anysuitable number of any suitable internal caches, where appropriate. Asan example and not by way of limitation, processor 502 may include oneor more instruction caches, one or more data caches, and one or moretranslation lookaside buffers (TLBs). Instructions in the instructioncaches may be copies of instructions in memory 504 or storage 506, andthe instruction caches may speed up retrieval of those instructions byprocessor 502. Data in the data caches may be copies of data in memory504 or storage 506 for instructions executing at processor 502 tooperate on; the results of previous instructions executed at processor502 for access by subsequent instructions executing at processor 502 orfor writing to memory 504 or storage 506; or other suitable data. Thedata caches may speed up read or write operations by processor 502. TheTLBs may speed up virtual-address translation for processor 502. Inparticular embodiments, processor 502 may include one or more internalregisters for data, instructions, or addresses. This disclosurecontemplates processor 502 including any suitable number of any suitableinternal registers, where appropriate. Where appropriate, processor 502may include one or more arithmetic logic units (ALUs); be a multi-coreprocessor; or include one or more processors 502. Although thisdisclosure describes and illustrates a particular processor, thisdisclosure contemplates any suitable processor.

In particular embodiments, memory 504 includes main memory for storinginstructions for processor 502 to execute or data for processor 502 tooperate on. As an example and not by way of limitation, computer system500 may load instructions from storage 506 or another source (such as,for example, another computer system 500) to memory 504. Processor 502may then load the instructions from memory 504 to an internal registeror internal cache. To execute the instructions, processor 502 mayretrieve the instructions from the internal register or internal cacheand decode them. During or after execution of the instructions,processor 502 may write one or more results (which may be intermediateor final results) to the internal register or internal cache. Processor502 may then write one or more of those results to memory 504. Inparticular embodiments, processor 502 executes only instructions in oneor more internal registers or internal caches or in memory 504 (asopposed to storage 506 or elsewhere) and operates only on data in one ormore internal registers or internal caches or in memory 504 (as opposedto storage 506 or elsewhere). One or more memory buses (which may eachinclude an address bus and a data bus) may couple processor 502 tomemory 504. Bus 512 may include one or more memory buses, as describedbelow. In particular embodiments, one or more memory management units(MMUs) reside between processor 502 and memory 504 and facilitateaccesses to memory 504 requested by processor 502. In particularembodiments, memory 504 includes random access memory (RAM). This RAMmay be volatile memory, where appropriate Where appropriate, this RAMmay be dynamic RAM (DRAM) or static RAM (SRAM). Moreover, whereappropriate, this RAM may be single-ported or multi-ported RAM. Thisdisclosure contemplates any suitable RAM. Memory 504 may include one ormore memories 504, where appropriate. Although this disclosure describesand illustrates particular memory, this disclosure contemplates anysuitable memory.

In particular embodiments, storage 506 includes mass storage for data orinstructions. As an example and not by way of limitation, storage 506may include a hard disk drive (HDD), a floppy disk drive, flash memory,an optical disc, a magneto-optical disc, magnetic tape, or a UniversalSerial Bus (USB) drive or a combination of two or more of these. Storage506 may include removable or non-removable (or fixed) media, whereappropriate. Storage 506 may be internal or external to computer system500, where appropriate. In particular embodiments, storage 506 isnon-volatile, solid-state memory. In particular embodiments, storage 506includes read-only memory (ROM). Where appropriate, this ROM may bemask-programmed ROM, programmable ROM (PROM), erasable PROM (EPROM),electrically erasable PROM (EEPROM), electrically alterable ROM (EAROM),or flash memory or a combination of two or more of these. Thisdisclosure contemplates mass storage 506 taking any suitable physicalform. Storage 506 may include one or more storage control unitsfacilitating communication between processor 502 and storage 506, whereappropriate. Where appropriate, storage 506 may include one or morestorages 506. Although this disclosure describes and illustratesparticular storage, this disclosure contemplates any suitable storage.

In particular embodiments, I/O interface 508 includes hardware,software, or both, providing one or more interfaces for communicationbetween computer system 500 and one or more I/O devices. Computer system500 may include one or more of these I/O devices, where appropriate. Oneor more of these I/O devices may enable communication between a personand computer system 500. As an example and not by way of limitation, anI/O device may include a keyboard, keypad, microphone, monitor, mouse,printer, scanner, speaker, still camera, stylus, tablet, touch screen,trackball, video camera, another suitable I/O device or a combination oftwo or more of these. An I/O device may include one or more sensors.This disclosure contemplates any suitable I/O devices and any suitableI/O interfaces 508 for them. Where appropriate, I/O interface 508 mayinclude one or more device or software drivers enabling processor 502 todrive one or more of these I/O devices. I/O interface 508 may includeone or more I/O interfaces 508, where appropriate. Although thisdisclosure describes and illustrates a particular I/O interface, thisdisclosure contemplates any suitable I/O interface.

In particular embodiments, communication interface 510 includeshardware, software, or both providing one or more interfaces forcommunication (such as, for example, packet-based communication) betweencomputer system 500 and one or more other computer systems 500 or one ormore networks. As an example and not by way of limitation, communicationinterface 510 may include a network interface controller (NIC) ornetwork adapter for communicating with an Ethernet or other wire-basednetwork or a wireless NIC (WNIC) or wireless adapter for communicatingwith a wireless network, such as a WI-FI network. This disclosurecontemplates any suitable network and any suitable communicationinterface 510 for it. As an example and not by way of limitation,computer system 500 may communicate with an ad hoc network, a personalarea network (PAN), a local area network (LAN), a wide area network(WAN), a metropolitan area network (MAN), or one or more portions of theInternet or a combination of two or more of these. One or more portionsof one or more of these networks may be wired or wireless. As anexample, computer system 500 may communicate with a wireless PAN (WPAN)(such as, for example, a BLUETOOTH WPAN), a WI-FI network, a WI-MAXnetwork, a cellular telephone network (such as, for example, a GlobalSystem for Mobile Communications (GSM) network), or other suitablewireless network or a combination of two or more of these. Computersystem 500 may include any suitable communication interface 510 for anyof these networks, where appropriate. Communication interface 510 mayinclude one or more communication interfaces 510, where appropriate.Although this disclosure describes and illustrates a particularcommunication interface, this disclosure contemplates any suitablecommunication interface.

In particular embodiments, bus 512 includes hardware, software, or bothcoupling components of computer system 500 to each other. As an exampleand not by way of limitation, bus 512 may include an AcceleratedGraphics Port (AGP) or other graphics bus, an Enhanced Industry StandardArchitecture (EISA) bus, a front-side bus (FSB), a HYPERTRANSPORT (HT)interconnect, an Industry Standard Architecture (ISA) bus, an INFINIBANDinterconnect, a low-pin-count (LPC) bus, a memory bus, a Micro ChannelArchitecture (MCA) bus, a Peripheral Component Interconnect (PCI) bus, aPCI-Express (PCIe) bus, a serial advanced technology attachment (SATA)bus, a Video Electronics Standards Association local (VLB) bus, oranother suitable bus or a combination of two or more of these. Bus 512may include one or more buses 512, where appropriate. Although thisdisclosure describes and illustrates a particular bus, this disclosurecontemplates any suitable bus or interconnect.

Herein, reference to a computer-readable non-transitory storage mediumor media may include one or more semiconductor-based or other integratedcircuits (ICs) (such, as for example, a field-programmable gate array(FPGA) or an application-specific IC (ASIC)), hard disk drives (HDDs),hybrid hard drives (HHDs), optical discs, optical disc drives (ODDs),magneto-optical discs, magneto-optical drives, floppy diskettes, floppydisk drives (FDDs), magnetic tapes, solid-state drives (SSDs),RAM-drives, SECURE DIGITAL cards, SECURE DIGITAL drives, any othersuitable computer-readable non-transitory storage medium or media, orany suitable combination of two or more of these, where appropriate. Acomputer-readable non-transitory storage medium or media may bevolatile, non-volatile, or a combination of volatile and non-volatile,where appropriate.

Herein, “or” is inclusive and not exclusive, unless expressly indicatedotherwise or indicated otherwise by context. Therefore, herein, “A or B”means “A, B, or both,” unless expressly indicated otherwise or indicatedotherwise by context. Moreover, “and” is both joint and several, unlessexpressly indicated otherwise or indicated otherwise by context.Therefore, herein, “A and B” means “A and B, jointly or severally,”unless expressly indicated otherwise or indicated otherwise by context.

The scope of this disclosure encompasses all changes, substitutions,variations, alterations, and modifications to the example embodimentsdescribed or illustrated herein that a person having ordinary skill inthe art would comprehend. The scope of this disclosure is not limited tothe example embodiments described or illustrated herein. Moreover,although this disclosure describes and illustrates respectiveembodiments herein as including particular components, elements,functions, operations, or steps, any of these embodiments may includeany combination or permutation of any of the components, elements,functions, operations, or steps described or illustrated anywhere hereinthat a person having ordinary skill in the art would comprehend.Furthermore, reference in the appended claims to an apparatus or systemor a component of an apparatus or system being adapted to, arranged to,capable of, configured to, enabled to, operable to, or operative toperform a particular function encompasses that apparatus, system,component, whether or not it or that particular function is activated,turned on, or unlocked, as long as that apparatus, system, or componentis so adapted, arranged, capable, configured, enabled, operable, oroperative.

What is claimed is:
 1. A method comprising: receiving a request torefresh a display for a refresh period, wherein the display is coupledto a touch sensor operable to detect touch input at the display; duringa first phase of the refresh period: refreshing a first portion of thedisplay; and while refreshing the first portion of the display,activating the touch sensor at a second portion and a third portion ofthe display, the second portion and the third portion being a halfscreen distance apart; and during a second phase of the refresh period:refreshing the second portion of the display; and while refreshing thesecond portion of the display, activating the touch sensor at a fourthportion and a fifth portion of the display, the fourth portion and thefifth portion being a half screen distance apart.
 2. The method of claim1, wherein the second portion of the display adjoins the first portionof the display.
 3. The method of claim 1, wherein the refresh period ofthe display is approximately 0.0167 seconds.
 4. The method of claim 1,wherein: an area of each of the first portion, the second portion, thethird portion, the fourth portion, and the fifth portion isapproximately one fourth of the display; and the fifth portion of thedisplay is the same as the first portion of the display.
 5. The methodof claim 1, wherein an area of each of the first portion, the secondportion, the third portion, the fourth portion, and the fifth portion isapproximately one sixth of the display.
 6. The method of claim 1,wherein an area of each of the first portion, the second portion, thethird portion, the fourth portion, and the fifth portion isapproximately one eighth of the display.
 7. The method of claim 1,further comprising: during a third phase of the refresh period:refreshing the fourth portion of the display; and while refreshing thefourth portion of the display, activating the touch sensor at a sixthportion and a seventh portion of the display, the sixth portion and theseventh portion being a half screen distance apart.
 8. A system,comprising: a display; a touch sensor coupled to the display andoperable to detect touch input at the display; and a controller coupledto the display and the touch sensor, the controller comprising logicthat is configured, when executed, to refresh the display in a refreshperiod and activate the touch sensor in the refresh period; whereinduring a first phase of the refresh period: the controller is configuredto refresh a first portion of the display; and while refreshing thefirst portion of the display, the controller is configured to activatethe touch sensor at a second portion and a third portion of the display,the second portion and the third portion being a half screen distanceapart; and wherein during a second phase of the refresh period: thecontroller is configured to refresh the second portion of the display;and while refreshing the second portion of the display, the controlleris configured to activate the touch sensor at a fourth portion and afifth portion of the display, the fourth and fifth portion being a halfscreen distance apart.
 9. The system of claim 8, wherein the secondportion of the display adjoins the first portion of the display.
 10. Thesystem of claim 8, wherein the refresh period of the display isapproximately 0.0167 seconds.
 11. The system of claim 8, wherein: anarea of each of the first portion, the second portion, the thirdportion, the fourth portion, and the fifth portion is approximately onefourth of the display; and the fifth portion of the display is the sameas the first portion of the display.
 12. The system of claim 8, whereinan area of each of the first portion, the second portion, the thirdportion, the fourth portion, and the fifth portion is approximately onesixth of the display.
 13. The system of claim 8, wherein an area of eachof the first portion, the second portion, the third portion, the fourthportion, and the fifth portion is approximately one eighth of thedisplay.
 14. The system of claim 8, further comprising: during a thirdphase of the refresh period: the controller is configured to refresh thefourth portion of the display; and while refreshing the fourth portionof the display, the controller is configured to activate the touchsensor at a sixth portion and a seventh portion of the display, thesixth portion and the seventh portion being a half screen distanceapart.
 15. A non-transitory computer readable medium comprising logicoperable, when executed by a processor, to: receive a request to refresha display for a refresh period, wherein the display is coupled to atouch sensor operable to detect touch input at the display; during afirst phase of the refresh period: refresh a first portion of thedisplay; and while refreshing the first portion of the display, activatethe touch sensor at a second portion and a third portion of the display,the second portion and the third portion being a half screen distanceapart; and during a second phase of the refresh period: refresh thesecond portion of the display; and while refreshing the second portionof the display, activate the touch sensor at a fourth portion and afifth portion of the display, the fourth portion and the fifth portionbeing a half screen distance apart.
 16. The non-transitory computerreadable medium of claim 15, wherein the second portion of the displayadjoins the first portion of the display.
 17. The non-transitorycomputer readable medium of claim 15, wherein the refresh period of thedisplay is approximately 0.0167 seconds.
 18. The non-transitory computerreadable medium of claim 15, wherein: an area of each of the firstportion, the second portion, the third portion, the fourth portion, andthe fifth portion is approximately one fourth of the display; and thefifth portion of the display is the same as the first portion of thedisplay.
 19. The non-transitory computer readable medium of claim 15,wherein an area of each of the first portion, the second portion, thethird portion, the fourth portion, and the fifth portion isapproximately one sixth of the display.
 20. The non-transitory computerreadable medium of claim 15, wherein an area of each of the firstportion, the second portion, the third portion, the fourth portion, andthe fifth portion is approximately one eighth of the display.
 21. Thenon-transitory computer readable medium of claim 15, wherein the logicis further operable, when executed by the processor or anotherprocessor, to: during a third phase of the refresh period: refresh thefourth portion of the display; and while refreshing the fourth portionof the display, activate the touch sensor at a sixth portion and aseventh portion of the display, the sixth portion and the seventhportion being a half screen distance apart.